hey,
with it being a baby.it could be anywhere,,cloths,pockets,SHOES!and they love to climb!you might want to try setting up a hooded heat lamp(with a clamp),with a 60 watt bulb,about a 12 inches off the floor,pointing downward,in a corner of a room,and have something under their for it ,to climb on and into,like a shoe,if it finds the warm spot,it stay their,Red Rats will lay for hours,under the heat,but think safety as well.nothing that could fall or rest on the lamp,paper material well away,this is why,nothing larger than a 60 watt,house bulb.

Joe