Did you end up finding something that worked?

My DS is 3.5 months and he is only having cat naps during the day (about 20 mins if I am lucky). I feed to sleep, but if i put him in his cot he will just wake up within a short while. If I hold him he can sleep for longer but with a toddler running around its just not possible.

Would love to hear what you tried and if it worked.