Being a stepmother

My partner has two children. When we were together, I was introduced to both. If you are to ask me, am I open to become a stepmother, the answer is yes. Not all women are open to be a mom to the children of her partner's ex. I totally understand that too. I love his children as my own and now they call me mommy. Honestly, me and his ex are in good terms. Despite me and my partner separating, she said we will make sure to speak and catchup, especially I also have his child. We will make sure, as mothers, we will try to keep the siblings close. May I ask your opinion regarding being a stepmother? Thank you so much!