We have decided to give LO my last name. He or she will grow up surrounded by people with my name, and will really be a member of the MyLastName family. Other than DH, we never spend time with anyone with his last name (his mother remarried and changed her name, his sister took her husband's name).
I think that is is still important to have DH's last name somewhere in our child's official name, if only to make traveling, registering for school and extracurriculars, etc. more simple. DH is on board, but does not care about having his last name as part of what the child uses on a regular basis.
Given this, would you give DH's last name as a second middle name, or a second last name? I know which way I am leaning, but wanted to get more opinions. I am particularly interested to hear from anyone who has a different last name from your partner - how did you handle the LN issue when it came to LO?