Table A1.

	Almost never or never	Seldom	Sometimes	Often	Almost always or always
My siblings respect my feelings.	○	○	○	○	○
My siblings encourage me to talk about my difficulties.	○	○	○	○	○
My siblings understand me.	○	○	○	○	○
When I am angry about something, my siblings try to be understanding.	○	○	○	○	○
I trust my siblings.	○	○	○	○	○
I can count on my siblings when I need to get something off my chest.	○	○	○	○	○
If my siblings know something is bothering me, they ask me about it.	○	○	○	○	○

Note: The sibling attachment subscale was adapted based on the IPPA (Armsden and Greenberg, 1987) to measure how much adolescents feel they can trust, communicate with and are supported by their sibling(s).