Bill & Ali BACK ON!

Bill Hader and Ali Wong are having a romance redux.

Giving it another go! Five months after Bill Hader and Ali Wong’s short-lived romance fizzled, the pair have rekindled their relationship. “They’d broken up because things got in the way, like work and kids, but they stayed friends and stayed in touch,” a source says of the Barry star, 44, and the comedian, 41. “Then they realized they had stronger feelings than either one knew.”

When Bill and Ali first dated, the former SNL star had recently split from Anna Kendrick, while the Beef star was fresh off a divorce from her husband of eight years, Justin Hakuta. (She calls the entrepreneur and dad to her daughters Mari, 7, and 5-year-old Nikki her “best friend.”)

But this latest go-round is much more than a rebound, suggests the source. “Bill and Ali genuinely care about each other. They like to be together when they can, they love their date nights, and they even have playdates with the kids.” (Bill shares daughters Hannah, 13, Harper, 10, and Hayley, 8, with ex-wife Maggie Carey.)

And while they love to “stay in and get takeout,” per the source, they recently jetted off on a romantic trip to Ali’s hometown, San Francisco, and are planning a more elaborate vacay, as Bill recently revealed. “My girlfriend and I were talking and she brought it up that I haven’t had a vacation in 10 years,” he noted. “So I think I need to go.”

Says the source, “Things are better this time around. They make each other laugh — and that’s one of the reasons they decided to give their relationship another try.” H