seems like you can only book for yourself or family members that you have to prove that they are family members!
Tips for redeeming miles
How to endorse bonus awards to family members
Bonus awards can be endorsed to the eligible family members : grandparents, parents, spouse, parents-in-law, brothers/sisters, children, son/daughter-in-law and grandchildren.
To register family members, please complete the SKYPASS Family Registration Form and submit it along with a copy of a government issued family register as a supporting document.