open two hilton cards(family member) and put points into same hilton account?

hi all,

just like the subject,

let's say i have 4 family members

if all of them open amex hilton card currently sign up bonus is 60,000.

can we put them in same hilton account? so i have 240,000 not four 60,000 separated.

i don't see why not but i just would like to make sure.

thank you in advance!