Live 3/6: AA in BB

[Frond]

LP table but a bit on the tight side at times. Pretty card dead so any of my raises are getting more folds than normal.

MP is older guy who doesn't raise at all PF and only raises on the river when his hand gets there.
SB is a beginner whose hand tremble when he has a hand and bets it so he is very easy to read.

5 limpers total including MP, SB complete, Hero looks at black Aces and raises, all call. Flop comes 2d 4d 9h, SB checks, Hero bets, folded to MP who calls, rest all fold. HU to the turn. Turn is 7c, Hero Bets, MP calls, River is 5d. Hero sees MP getting out chips, Hero checks, MP bets, Hero calls.

Standard or Vbet river? He sure appeared to be drawing here and made a hand.