Green card for H4-expired spouse of Green card holder

[immihelp]

Hi, I was going through your website for some information but since I couldnt find it, I would appreciate it if you could respond to my query. I am an H1b visa holder, and my husband is here on an H4 visa. My mother, a US citizen, applied for my green card and that petition was approved a few months ago. My H1b expires soon, and if my green card comes through by then, my husband's H4 expires. What do I do to get his Green card processed soon? Will he be illegal here if his H4 expires?

[immihelp]

You will have to petition for his green card, on F2 basis. That takes around 5 years. He can't stay in the US until then, unless he qualifies for H1 etc. on his own.