Gwen Stefani and Blake Shelton appear to grow closer every day. Blake has even established relationships with Kingston, Zuma, and Apollo–Gwen Stefani’s children with Gavin Rossdale.

This weekend the celebrity couple shared their love with Gwen’s youngest son Apollo, at a cowboy-themed birthday bash in honor of his upcoming second birthday.

“[They had their] arms around one another, and [gave each other] little kisses on the cheek,” a source tells Entertainment Tonight. “Blake was very hands-on with the kids, playing and walking around with them.”

.@BlakeShelton helped @GwenStefani celebrate her son's birthday with lots of PDA! ? https://t.co/sxviLn61yh pic.twitter.com/zJX0fq6kfo

— EntertainmentTonight (@etnow) February 23, 2016

As expected, Blake Shelton and Gwen Stefani weren’t the only celebrities at the birthday party. Jessica Alba and her husband, Cash Warren, and their two daughters, Honor and Haven, attended the bash. Rachel Zoe and her two sons, Skyler and Kaius were on hand for the fun, too, as was late night host James Corden.

Gavin Rossdale was the celebrity many expected to attend Apollo’s birthday party, but he wasn’t there. Perhaps he will attend whatever might be planned for the little boy on February 28–his actual birthday.

Fans love seeing Gwen Stefani and Blake Shelton together. They especially love seeing Blake with Gwen Stefani’s children. Rumor has it he wants kids, and that was part of the reason for his split from Miranda Lambert, although neither has confirmed that rumor.

Do you expect Gwen Stefani and Blake Shelton will one day create a family of their own? The two have been officially dating since fall, so there’s certainly plenty of time to plan for the future.

Aw! Blake Shelton and Gwen Stefani shared a sweet kiss at her son's birthday party! Pic: https://t.co/wAfTWgK1KZ pic.twitter.com/jgmEWoeWEQ

— HollywoodLife (@HollywoodLife) February 22, 2016

In November, shortly after confirming they were a couple, Blake was asked if he and Gwen Stefani were starting a family.

“I think it’s awfully early to be talking about that, don’t you?” he replied.

How might Blake reply if asked that same question today?