HELP PLEASE! 07 Hyundai Sonata alternator trouble need advice badly

**No **any help is beyond appreciated!
Ok I have a 07 Hyundai Sonata ‘Limited’ , just 46k miles used for light use. Recently it broke down twice each time to both times it took a bit to jump the battery, on the 3rd time it broke down I had gotten a too of line brand new battery. Everything was fine for about 3 days when it comes out again for the last time, got it towed to mechanic where the guy then replaced the alternator. It’s a been just under a month now , when I took the car in for inspection, my brother took the car there as my 4 year old was sick, so my mechanic the one who did the work replacing the alternator tells my brother that the alternator is leaking? My brother told me this when he drove the car back to where I live to drop it off, so the mechanic tells him this and still let him drive it back to me a good 11-15 min away, roughly. My brother is more of a woman than me he knows nothing about card what so ever still lives with my mom doesn’t pay bills etc etc. So he’s useless but I was wondering if the mechanic let him take it does that mean it’s safe to drive in any capacity? Any mechanics reading this, just replacing an alternator why would it then be leaning? Was something not done correctly or overlooked and perhaps may be why it hasn’t been treated like a big deal? Is it dangerous to be driving at all? I have a 4 year old and 6 year old I am afraid of driving my son to school in the morning the mechanic hasn’t spoken to me I try to call and have to.leave messages… is this serious? If it’s driven at all even minimally possible to make something worse? Also with It being a good 2 1/2 from replacement from the same man is there any, for lack of better terms, warrantee if you will, that since he replaced it that within reason would be do able to fix it? Because I’m not understanding why he had just replaced it I paid very good.money that I don’t really have as well as a pretty nice too on top of it all? Or is this something that is a costly repair? The most I ever run it is to get my kids to school in an which is hardly 1 or 2 miles away and once a week or so to a store which is also in a 1 mile radius. I am nervous about doing necessary things being I always have my.young children in car and also I am afraid of doing more damage by starting it at all
Online searching isn’t offering much help or answers to seriousness or safety or cost or exactly what that even means ‘alternator leak’. The car itself runs normal for the most part but there are times usually on accelerating or deceleration almost catches for a moment, like feels like a soft kick the best way to try to explain is like a for just a second like pull foot off gas pedal. I’m.sorry that’s horrible I can’t figure out how to put into.wordsm but even still that’s about it I mean nothing like when it was kicking back when it all went bad…pleaae any thoughts or advice anything at all I’d greatly greatly appreciate ! Unfortunately this website as I’ve tried writing this isn’t appearing at all I can’t tell if things misspelled or messed up I can’t see anything, I’m hoping my phones auto correct has kicked in some, I’m hoping it’s legible enough and that after it’s posted I can look on different \ full page and edit. Please know if it’s the worse of the above I am literate and will try my best to make corrections. Thank you so.much for your time anything at all would be appreciated! Thanks, blessings <3

Hey there, I’m not a mechanic yet but I am studying Lvl3 in Motor Vehicles at College and I have never herd of an Alternator “leaking” as there is no liquid inside the alternator, the mechanic could of been saying that its not giving enough power to the battery as it should. But if this is the case than the cables connecting the alternator to the battery would be rusty on the connectors (the parts that are actually on the battery and alternator).

The car would be perfectly fine to drive you children to school, if it is only a small trip to school, than I would drive around for another 10-15 mins so that it can charge the battery up. The battery itself is only used to start the car, once the engine is started than it will use the alternator to run the electronic components for both the engine and the inside of the car (radio, interior/ exterior lights, charging your devices from the cigarette lighter port. If you have a voltmeter or a multi-meter than you can check if the battery is charging, set the device to 20 volts DC and check the battery when the car is on, you wont get an electric shock ( it should go to 13.6 volts when charging), if it is lower than the charging voltage on the battery, then check the connecting cables voltage, if they are low then check the resistance of the cables in ohms, if it has thousands of ohms resistance than it is the cables and not the alternator.

I hope that this was helpful to you in any way, reply back to me if it worked or not.

You really need to talk to the mechanic, your brother did not relay the message correctly. You mechanic does speak English I presume? The on;y time a mechanic would say an alternator is leaking would be if English is not his first language and he is having trouble coming up with the right term.
He may have said your battery is being drained, but that is probably not the fault of the alternator.
The car simply needs to be driven more than a mile or two. That isn’t long enough for the alternator to replace the current used to start the car and the maintenance current used to run the computers that control a modern car even when it isn’t running.
If you have a garage with electric outlets, you could use a battery tender ( a small battery charger that will not overcharge your battery )
Battery Tender is the brand I am familiar with but I am sure that other brands exist.

Well, maybe the mechanic has a strong electrical background. If a diode inside the alternator shorts, it can drain the battery very quickly. A damaged diode can also happen where it still drains the battery but not as quickly. This type of damage is often referred to as a “leaky” diode. So maybe that is what he was referring to. Either way, that kind of loss can be measured and verified so that is where I would start (versus just swapping out the expensive alternator)…

Actually, there are a few high end cars that use water cooled alternators

But this isn’t one of them . . . I just looked on rockauto, and both the 4 cylinder and V6 Sonata use very conventional alternators

What’s the voltage measure at the battery posts when the engine is idling? That’s the place to start with alternator problems. About the only way an alternator could leak is the bearings might leak a little grease, which I’ve never heard of happening, but even that wouldn’t be a problem unless it results in an alternator related noise.

Is the alternator light in the dashboard lit?

I agree with the others that you need to talk to the mechanic. If the alternator is defective, is there a warranty? It’s only a month old, correct?