L.K.
I have boy/girl twins and the book I read was Healthy sleep habits happy child.It tells you that the baby should be up no more than 2 hours at a time at that age . At 1 month old all they do is sleep and eat.They don't have the attention span yet to keep them awake to play yet. So don't worry ,they are doing great just need their sleep right now. When they get to about 3 or 4 months you will notice they will want some interaction.Good LucK!