Best way to ask a cancer a favor?

I understand that it will sound strange, but my friend's family is running out of ideas.

The mother is a cancer. Mother of 3 sons, they all get along well except the part where Cancer mom is kind of overly emotive when it comes to some things such as when she is not included in some young adults dinner dates or when her younger son is planning a trip with his friends and keeps saying how alone she will feel when he will be gone. She also nags when they go grocery shopping with her, because they didn't buy what she wants. She is into guilt trips a lot and they say it's not fun to deal with her.

She is an amazing woman though. She is a good listener, always remembers birthdays and anniversary. Always thinking about others, so this situation is confusing for all the family.

Cancer mom needs to sign very important papers and she is lying to all about them and the reason why he didn't sign them yet. They're not sure why, but they think it's because she wants to keep her family close to her.

She is half American, but has yet to ask for American citizenship. All her 3 sons has been asking her for years to sign the paper in order for her to get it, and then allow her sons to ask said their citizenships.(They are all Canadian)

It's been going on for years, and whenever they ask her. It's always a different excuse.
She needs to ask this cousin for information about her family, or can't find the papers, or forgot this, that.

And when they confront her about the fact that she talks to said cousin once a week, there's always a reason why she forgot. When they all know she is lying.

So here I am asking you all lovely Cancer what they should do in order for her to sign the papers.

They tried confronting her, they tried bugging her once a week and ask to remind her.

Always the same thing..

😢

Putting myself in her shoes, if I wasn't doing something, there would be a very good reason and one I wouldn't necessarily want to share? So there has to be a good reason, I mean good..important, some piece of information/history/story. She's hiding something. My thought, but for good reason in her mind. She may think she's foreseeing something if she signs.

I dnt no what to say.this reminds me of my scorp mom for some reason.sound like shes lonly. My scorp mom give me a hard time when I left her house for the first time. This just sounds like a women who dont want to let go. She needs to be reasure be everyone.she need to no she well love so she can let go.