Ashlee, Pete and Bronx Mowgli Wentz Sign Autographs

Sunday was family day for Ashlee Simpson and Pete Wentz.

The two took son Bronx Mowgli, whom they welcomed last November, to the Elizabeth Glaser Pediatric AIDS Foundation's "A Time For Heroes" celebrity carnival.

As Pete helped locals customize T-shirts, the new Melrose Place star stood by his side, making faces and smiling at Bronx, whom she held in her arms.

He sure is a little cutie ...

Rumors that Pete Wentz got Ashlee Simpson pregnant a second time appear unfounded, which is probably for the best. The two have their hands full with one bundle of joy - and made a T-shirt especially for Bronx at the charity event.

Pete - who celebrated his 30th birthday Saturday in Las Vegas - also was on daddy duty at the event, holding Bronx as Ashlee chatted with some fans.

Ashlee began cracking up when a young girl approached her for an autograph and Bronx tried grabbing the girl’s book. Ah, to be a cute young mom.