Article continues below advertisementRob Kardashian is back on social media!On Wednesday, November 5, the reality star returned from a one-year hiatus away from Instagram to send his mom, Kris Jenner, birthday wishes.Article continues below advertisementRob Kardashian Honors Mom Kris JennerSource: @robkardashianofficial/instagramRob Kardashian returned to Instagram to wish his mom, Kris Jenner, a happy 70th birthday.