California: Ending lease, tenant not responsive.

[Linh Vuong]

Hello, I'm fairly new to the real estate community and rented my home to a couple last year September 2018. My son and his wife are expecting a baby in March and I wanted to give them the place to stay, since the current residence they reside is not big enough for their growing family.

The tenants lease ended this year Oct 1,2019. I sent them a certified letter and it shows delivered on October 2nd, 2019. The notice states I am giving them 90 days (I know I need to give at least 60 days, but my son doesn't need it until January) to find a new place to live. I have not heard back from them so I sent them a short text message just asking them to confirm they received the notice. The text message shows he read the text, but its been 48 hours and he has yet to respond to my text. 

I would like some advice on what to do next. Do we wait until the end of December to reach out again, or do we give it a few weeks and try to reach out once more for confirmation? Worst case scenario, if they never respond and dont move out come December 31, what do I do next?