Michael Strahan, whose smiling face has become a regular fixture on Good Morning America, has been missing from the show this week.

As for why he has been absent, Strahan is likely at home with his daughter Isabella Strahan as she reaches a huge milestone in her cancer battle. The 52-year-old didn’t confirm whether or not Isabella was the reason for his break from the show, but the 19-year-old recently revealed that she would be going through her final round of chemotherapy at the start of the summer.

Isabella keeps her fans regularly updated through her social media and YouTube vlogs. At the end of May, she shared that she completed her third round of chemo and that the upcoming treatment would potentially be the final one.

The day before her last day of the third round, Isabella told her fans, “Tomorrow’s really my last day of chemo…It’s crazy. And then it’s my last cycle and I’m done, it’s like insane.” Along with chemotherapy, Isabella has also gone through a number of brain surgeries, starting with one at the end of last year after her cancer was first discovered.

Strahan has been quite open about his daughter’s journey, telling Good Morning America in February, “It is tough to see her go through it, but I know she’s a tough young lady and she’s going to make it through it.”

When Isabella was dealing with the early diagnosis, surgery and treatment last October, Strahan was noticeably absent from Good Morning America, causing some fans to worry. He later returned and explained the struggles his family was going through, and since then, he has maintained a relatively regular work schedule while still supporting Isabella through her treatment.

In Isabella’s most recent update, she shared a look at the family’s quality time together with Strahan and her twin sister, Sophia, as they celebrated the twins’ 19th birthday months late. This was due to the fact that, on their last birthday, October 28, Isabella was in the hospital recovering from her first brain surgery.