In 2020, quarantine home confinement measures were implemented in Spain to control a pandemic for the first time. The objective of this study is to assess both the psychological and social impact of that “lockdown” on different age groups of children and adolescents, and also the different strategies adopted by families in that situation. We collected data via an online questionnaire answered by 850 participants, parents of young people aged between 4 and 18, between 24th April and 8th May 2020. Our results show that living in a home smaller than 80 m2 is associated with an increased risk of presenting clinical symptoms of emotional or behavioural distress, with an odds ratio of 2.54 (95%CI: 1.07 - 6.02), p = 0.034; while increased age is a predictor of better psychological functioning during lockdown: coefficient of 0.25 (95%CI: 0.07 - 0.41), p = 0.004. Moreover, age is also a marker of higher scores on the scale of psychological symptoms, with a coefficient of 0.02 (95%CI: 0.01 - 0.04), p = 0.005. To conclude, younger children present poorer behavioural and emotional functioning and more symptoms of emotional distress than adolescents during lockdown. Living in a small home is a risk factor for presenting clinical symptoms. These findings should be taken into consideration when planning for future home confinement episodes and when considering preventative strategies in the realm of mental healthcare.