Syftet med denna kvalitativa studie var att ur ett retrospektivt perspektiv undersöka biologiska barns upplevelser av att växa upp i familjehem. Fokus var deras upplevelse av att ingå i en familj med fostersyskon, samt deras upplevelse av socialtjänstens stöd. Empirin grundades på enskilda intervjuer med fyra nu vuxna biologiska barn i familjehem. Vid analysen användes barndomssociologi, barnperspektivet samt Harts delaktighetsstege. Resultatet visade att informanterna upplevde att socialtjänsten inte involverade dem i familjehemsprocessen. Graden av delaktighet grundades istället på föräldrarnas agerande. Samtliga informanter upplevde tillgängligheten till sina föräldrar som bra, hälften hade dock önskat mer tid och uppmärksamhet. Majoriteten av informanterna beskrev att de tagit ett stort ansvar för sina fostersyskon, påtvingat eller på eget initiativ. Resultatet indikerar också att erfarenheten av att växa upp med fostersyskon utvecklat empati och förståelse för andra hos samtliga informanter. Resultatet visar också att majoriteten av informanterna upplevde stark samhörighet till sina fostersyskon, att de hade goda relationer till dem och tyckte om att ha fostersyskon. / The purpose with this qualitative study was to investigate biological children’s experience of growing up in private foster care homes. This was done through a retrospective perspective, and the purpose was to focus on the children’s experiences of being in a family with foster siblings, and the support they perceive that they received from the social services. The empirical data is based on four interviews with adults that during their childhood were growing up as biological children in private foster care homes. When analysing the result, the childhood sociology perspective, the child perspective, and Hart’s ladder of participation were used. The result showed that the interviewees did not perceive the social services incorporating them as biological children in the foster care process. The level of participation was instead determined by the parents’ intuition. The informants perceived their relationship to their parents as good, however, half of them had wished more time and more attention. The majority of the participants described that they took a great deal of responsibility for their foster care siblings, either voluntarily or involuntarily. Further on, the result indicated that the interviewees had, thanks to growing up with foster care siblings, developed empathy and a more profound understanding of others. Finally, the result showed that the majority of the informants felt a strong bond to their foster care siblings, had good relationships to them, and liked having foster care siblings during their childhood.