If you use tweezers or rubbing alcohol you will make the tick spit the blood back in your sister with all the pathogens with it, this is what causes diseases.
With the right tool the tick is very easily removed with a very low risk of infection.
And properly discard of the tick so it cannot come back. Suggested methods are submersing it in strong alcohol, pulverizing it between hard surfaces or simply lighting the fucker on fire. The guide I've read spoke especially against stepping on them because the ground is uneven and your shoe soft enough to give them a chance to survive. Oh and flushing them down the toilet also gives them a good survival probability.
I prefer the fire approach, fuck those little bastards and diseases they carry. No one survives getting their ass heated to over a thousand degrees Celsius.
Some spider bites, and definitely tick bites could be a big issue. As someone else mentioned with the circle around the bite. Get it checked out. Save the tick if you pull it out and get it tested. Lyme disease is not something to be taken lightly.
The NSFW isn't to be taken literally. In this case it''s a "I don't want to spontaneously see your weird ass bug and vampire kink bait when I didn't subscribe to anything that would reasonably have it, thanks". The tag gives viewers the ability to opt in.