Thanks guys. I'll go with some Portra 160. The baby is 3 months now and been home a while. They have a new house with lovelly big windows and big rooms so the light gets difused arpound the room nicely. Before they asked me I was sat in various rooms in their house thinking "I'd get some great photos in this house with this light" and then the question arose :-)
Funny the issues raised about 400H - I am having problems with some 800Z but that is a new thread I am about to open.