If keys get locked inside your car, can you unlock it by using cellphone?

I received an email that said “if you lock your keys in the car and the spare remote is at home, call someone at home on their cellphone from your cellphone. Hold your cellphone about a foot from your car door and have the person at your house press the ‘unlock’ button while holding it near the cellphone on their end”.
I tried it and it didn’t work, but I thought I would see if anyone else has had success with this.

How do I convince my parents to let me have a cellphone?

My mom put the idea in my head but changed her mind! I’m asking for a cheap simple phone and my bills are $10 per month! I don’t care what kind of phone just I want a cellphone! She bought my brother a phone but he didn’t want a cellphone she just got him one but I can’t have one and I’ve been begging for one! And now I’m in highschool it’s kinda something I need!! Our school wifi isn’t great so I can’t text her from my iPod it only works in one place! Once I forgot to tell her I had a short day at school and its weird coming up to strangers and asking to borrow their phones to call her :(