Kate Middleton and Prince William are "more open" and "talk about their relationship together" amid her cancer journey, a source tells PEOPLE.

When Kate Middleton celebrated her 43rd birthday on January 9, her husband Prince William wrote a tender message and shared it on the couple’s public Instagram account. According to royal expert Ingrid Seward of Majesty magazine, the display of affection was a sign that the couple has grown closer following Kate's cancer diagnosis in early 2024.

Angela Terry, a lung cancer patient, tells PEOPLE that Kate's "gentle eye contact" and " level of connection " left an impression. The royal also reassured Rebecca Mendlesohn, who is in a trial for metastatic cancer, and wrapped her in an emotional embrace.