Ryan Blaney’s sister’s close friend Daryn Mosack shares a heartwarming birthday post for her

Daryn Mosack, friend of 2023 NASCAR Cup Series champion Ryan Blaney's sister, Erin, took to social media to wish her friend a happy birthday. Erin recently turned 28 years old and took time to celebrate with those closest to her.

Mosack and Erin have been seen together on Instagram often, showing that they're close friends. The former took to Instagram on Thursday, posting photos from the birthday party. Her caption penned a unique hashtag to signify how old the latter is, adding:

"Can we have a birthday party every Wednesday??? happy birthday @erinblaney 🍰💙🍾🦋 #twentyATE"

Daryn Mosack is the wife of CRAFTSMAN Truck Series driver Connor Mosack, who pilots the #81 McAnally-Hilgemann Racing Chevrolet full-time. In 13 starts, Mosack has four top 10s and one top-five finish.

In honor of her birthday, Erin took to Instagram to reflect on the last year. She wrote:

"If I wrote a letter to this past year, I wouldn’t know where to start. I would want to say I was mad because it definitely broke my heart. But I change my mind and say Thank You because of how much I’ve grown. Everything has been a blessing because it taught me grace. I now have so much color in my face! 🥰"

Erin's brother, Ryan Blaney, pilots the #12 Team Penske Ford full-time in the Cup Series. He's amid his 10th full-time Cup campaign and his eighth season at Team Penske. He's teammates with fellow Team Penske drivers Austin Cindric and Joey Logano. The North Carolina native has 13 career victories and became the Cup Series champion in 2023.

After four races, Blaney currently sits fourth in the Cup Series standings. The driver of the #12 finished seventh in the Daytona 500, fourth at Atlanta, 19th at Circuit of the Americas, and 28th at Phoenix Raceway.

Ryan Blaney said, "all bets are off" in leadup to Sunday's NASCAR Cup race at Las Vegas

The Las Vegas Motor Speedway is the site of the fifth race of the NASCAR Cup Series season this Sunday. Ryan Blaney made his intentions known for the 267-lap event in a recent social media post.

Blaney took to Instagram and made it known that he's going to leave it all on the track this Sunday, penning the caption:

"This weekend, all bets are off. Let us deal you in this Sunday at 3:30 PM ET from Sin City."

Ryan Blaney has finished in the top 10 in two of the last three Las Vegas races, most notably third in last year's spring event. That third-place run is Blaney's best finish at the 1.5-mile track as he's seeking his first win at Las Vegas. The driver of the #12 is searching for his first win of 2025 this weekend.