Change in routine affecting sleep ?

[agirlcalledsandoz]

My DD is 16 months old. She has basically been sleeping through the night for the past few months. However I have recently given up work to be a SAHM and she has taken to waking at about 1am every night ! I give her a drink of water and she goes back down. She naps for 2 hours during the day from 12-2. Is this too much or could the change in her routine be making her wake ? She was previously with MIL.