Stiff upper lip, and all that.

Prince William is doing the best he can to keep a proverbial lid on things as he endures his wife Princess Catherine‘s scary and unexpected battle with cancer. That his father King Charles is also dealing with a cancer diagnosis has made things doubly difficult for the 41-year-old Prince of Wales and the rest of his family. And in response to these terrifying challenges, he’s closing ranks.

People spoke to royal sources early on Thursday morning, and they revealed that Kate Middleton‘s beloved husband is “not leaning on too many others” as his wife and father both fight cancer. Instead of opening his circle for a wide array of support, William has taken things internally to show private emotional support for Kate — and most especially for their children Prince George, 10, Princess Charlotte, 9, and Prince Louis, 6.

A second royal source confirmed that first insider’s claim by noting William is relying heavily only on “the nuclear family unit” of their immediately family of five. He does have key support from two other people outside of their nuclear family, though: Kate’s parents Carole and Michael Middleton.

William has always been close to Carole in particular ever since he and Kate got together. And now, that bond is apparently flourishing behind closed doors despite the development coming under very difficult circumstances. The insider explained:

“I imagine he is leaning on them really hard.”

As for Princess Catherine, she too has (obviously) pulled momma Carole in even closer than ever:

“You can let down your barriers when it’s your mother.”

Ugh. We can understand that. No matter how old you get, you always need your mother when times get tough.

As you may already be thinking, these new insider quotes track pretty closely with our reporting from Wednesday in which William was revealed to be “digging deep” for strength amid his 42-year-old wife’s uncertain health battle. But one thing all this is not affecting is how William goes about his long-term outlook regarding the monarchy. These dual health crises haven’t forced a newfound focus on the Prince of Wales’ fate, an insider explains, because he has long been prepping for that part:

“It won’t have suddenly made him think more about the future role. That’s something he has thought about for years, if not decades.”

Makes sense.

As for his fractured relationship with Prince Harry, that is one spot in which Wills could use some help — but as of now, he ain’t gonna get it. Royal biographer Ingrid Seward sadly explained to the mag:

“William would have always imagined he would have Harry alongside him. Going forward, that puts responsibility more on William and his family. There is no one else to take the slack.”

Oof. Clearly, it’s a lot. Royal or not, battling a cancer diagnosis in the family — and now two of them, to boot — is a massive and daunting challenge. Sending love and light!