Jessica Simpson & Tracee Ellis Ross Are Glam "Sisters" at Big Family Celebration—See the Pics!

Ashlee Simpson Ross and Evan Ross' sisters celebrate actor's 27th birthday with family just one month after welcoming daughter Jagger Snow Ross

By Rebecca Macatee Sep 01, 2015 8:53 PMTags

#sisters

A photo posted by Tracee Ellis Ross (@traceeellisross) on

Can we please join the Simpson-Ross extended family? It looks like they're having the most fun!

Evan Ross turned 27 on Wednesday, and over the weekend wife Ashlee Simpson Ross, sister Tracee Ellis Ross and sister-in-law Jessica Simpson were among those celebrating the birthday boy (and brand new daddy)!

Tracee, 42, and Jess, 35, got all glammed up for the occasion. The Black-ish star and the fashion mogul might not be technically related (they're each a sibling of the other's sibling-in-law), but they clearly fit right in together! Tracee Instagrammed a chic, sequin-filled photo of the twosome pre-party with the hashtag #sisters!

I love my sister so much @traceeellisross . She is what it means to be cool!!

A photo posted by Evan Ross (@realevanross) on

Jessica's biological sister Ashlee, 30, looked relaxed yet stylish at her hubby's b-day bash! Evan's special day came just one month after the couple welcomed daughter Jagger Snow Ross.

A source tells E! News that Evan's party was a great time and, though Jagger slept right through it, the birthday boy and his wife couldn't stop talking about how great it's been to be parents together and how much fun they're having as a family.

Meanwhile, Ashlee's 6-year-old son Bronx (with ex Pete Wentz), true to his showbiz roots, was the star of the night, performing a cute dance routine for the revelers.

And of course, Evan made sure to show some love to his big sis Tracee! He Instagrammed a sweet photo showing him planting a kiss on her cheek, gushing, "She is what it means to be cool!"

That's some sweet sibling love! Evan and Ashlee both come from tight-knit families, so hanging out with relatives happens quite a lot. This includes, of course, quality time with Jessica and Eric Johnson's 3-year-old daughter Maxwell and 2-year-old son Ace.

My beautiful wife @ashleesimpsonross. Love her so much!!! #birthdaypartyfun

A photo posted by Evan Ross (@realevanross) on

Jessica and Ashlee's mom Tina Simpson is in luck, too, with four adorable grandchildren. Joe Simpson's ex got engaged earlier this year to Jon Goldstein, the owner of a high-end landscaping company based in L.A. No word just yet when Tina's wedding will be, but we can think of two potential ring bearers and a darling flower girl, too! (Sorry, Jagger: Unless grandma Tina waits a while, you'll probably still to be too small to toss any petals...)

Also, Jessica and Ashlee both got married last year, so they'll no doubt be happy to share any planning tips and tricks with their mom on her special day.