What happened to the schedule?!

When boo turned 4 months her schedule went out the window. She used to take 2-3 naps during the day and sleep about 6-7 hours. Now a days she is taking no naps and sleeping only every 3 hours. WHAT?!?! If you know me, you know I google everything. So her I go and to my surprise babies who are 4 months lose their sleep schedule! Even Nicole says Elsin is just now getting back on her schedule and she's almost 5 months. Why do babies do this? I love when Sophia is awake and even better when she is happy but at night I want to sleep. I don't want to miss any waking moment with her but at the same time I find myself saying I can't wait for 5 months.