(1)证明:∵四边形ABCD为平行四边形,
∴AD∥BC,AD=BC.
∴∠DAE=∠AEB.
∵AB=AE,
∴∠AEB=∠B.
∴∠B=∠DAE.
∵在△ABC和△AED中,
,
AB=AE ∠B=∠DAE AD=BC
∴△ABC≌△EAD.
(2)解:∵AE平分∠DAB(已知),
∴∠DAE=∠BAE;
又∵∠DAE=∠AEB,
∴∠BAE=∠AEB=∠B.
∴△ABE为等边三角形.
∴∠BAE=60°.
∵∠EAC=25°,
∴∠BAC=85°.
∵△ABC≌△EAD,
∴∠AED=∠BAC=85°.