This is a funny joke, lol, but in the real world make sure you don't take your birth control with orange juice or any kind of acidic drink- it cancels out the effectiveness of them. The same with prescription antibiotics- a lot of those cancel the effectiveness too!
***The More You Know**
My doctor never told me that grapefruit juice or antibiotics cancels out the effectiveness of birth control pills until I had a scare a year ago! I was sooooo mad!
Well yes, but the grandma is behaving unethically by ditching her granddaughter to unknowingly ingest these chemicals. What if the granddaughter is allergic or has her own secret prescription or, for some reason, wants to conceive. To be ethical able this, the grandmother should have The Talk with her granddaughter and offer the prescription for birth control.
***The More You Know**