Kate Gosselin is celebrating the birthday of her sextuplets, but one of the kids was missing once again for their birthday that will be seen on an upcoming episode of "Kate Plus 8." It turns out that Kate's son Collin wasn't there. Radar Online shared the details about what happened and why he was missing from the big camping trip that the family took.

What big trip did Kate take the kids on?

They family went on a camping trip, but it would be more like glamping, which is glamor camping. A mini-season of "Kate Plus 8" is coming up and in this new season, you will get to see the trip that Collin had to miss.

They are seen playing archery tag, which they did on the show before. They also have smores and cake. The older girls Cara and Maddy actually decorated up the tent for them to go glamping and it looks like they did a great job with it. You will get to see it all on the new season of the show, which looks like it is going to be great so far. The fans can't wait to see the Gosselins on television once again.

Why did Collin Gosselin have to miss the trip?

Collin has been living at a behavioral health facility due to anger issues. Kate shared that it was a hard decision for her, but fans assumed he would eventually be invited to come back home. Kate shared that her son needed help learning how to deal with certain things.

Collin Gosselin isn't even allowed to leave for things such as Thanksgiving, but he has been there a while. Nobody knows why it has taken him so long to get through the program. An insider shared that Collin allegedly has really big anger issues and will lash out, plus says that it all started when his parents split.

Last year on his birthday, Kate talked about it and said "He needs to be in an environment to help him learn the skills and gain the insight that he needs to be the best Collin that he can be.

So, birthday party without Collin – tough for them, tough for mom.” It had to be hard on Kate once again this year. No word on what went down for Collin at the home, but hopefully he got to celebrate his birthday there and maybe his family even got the chance to visit him.

Are you shocked to hear that Kate Gosselin's son Collin wasn't there once again?

Do you think that she should have brought him home for the party? Sound off in the comments section below on your thoughts, and don't miss new episodes of "Kate Plus 8" when it returns to TLC. The new episodes will start airing on July 10, but it will just be a small season.