10 years route to ILR

Hi Gurus
I read of this forum for long time. I would like to get help from Gurus via this forum now.

I came to U.K on end of June 2008 on a Student Visa. After I applied for PSW, entrepreneur. Now applied for entrepreneur extension and I received the letter from home office that my visa has been granted. I am waiting the for the BRP.

I applied with two dependants, husband and 5 years old son he was born in U.K. During this entrepreneur extension application in process, I had a baby he is now 2 months old. We are planning to travel to our country as soon as earlier as my mother is in bed for more than six months.

Can I apply for ILR 28 days before in one day service. Do I need to apply for 2 months old as well or do I need to register him as British citizen, after I granted my ILR. Is there any other obtion for my situation.

Thanks in advance for the advices.