Hi there Caro, Julia was 7 pounds 8 oz and she fit into 0000 for 2 weeks and was in 000 for 2 1/2 months they were a bit big from the start after 2 weeks after birth but has now just gone to 00 at 3 months. I would buy the wondersuits they are the best for April kind of weather, Im guessing its a bit like September weather when my baby was born? I wouldnt buy anything heavier for them to wear while at home or when sleeping if the baby will be wrapped. We had 5 x 0000 and 8 x 000 wondersuits that were great and also 5 baby pumpkin patch body suits which have been great.