I have three stars on the back of my neck and then I have my three nephews first initials in a tribal heart on my left should blade. You could do just their initials on the back of your neck and make it look really elegant of more
abstract.
BTW I'm really sensitive on the back of my neck and it didn't hurt at all!
Here is my tatt of my nephews initials... It's an L for Luke, An A for Alexander and an A for Austin.

I eventually want to get one for my step-son and daughter and hopefully the child DH and I will have together in the future!
Here a few other examples that I found.

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I love Rihanna's neck tattoo. You could do their names in a design like this.

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You could also do their zodiac symbols. Or birth month flowers.

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