Study investigates how having a pet in early childhood can influence emotional development

A research team from the INMA Project (Childhood and Environment) has analyzed how pet ownership during early childhood may be related to emotional and behavioral well-being in children. The results suggest that both the type of pet and the timing of coexistence may have different effects on emotional development.

The INMA Project, coordinated by the Spanish Consortium for Biomedical Research in Epidemiology and Public Health (CIBERESP), is a Spanish multicenter cohort designed to study the impact of environmental factors (air, water, diet, surroundings) on child development.

The study was conducted by researchers from Fisabio Foundation (Valencian Regional Ministry of Health), CIBERESP, Universitat de València, University of Oviedo, University of the Basque Country (EHU), Universitat Jaume I of Castelló, the Barcelona Institute for Global Health (ISGlobal), and IIS Biogipuzkoa.

Published in the World Journal of Pediatrics under the title “Impact of pet ownership in early childhood at ages 1 and 4–5 years on mental health at ages 7–8: findings from the INMA project,” the study analyzed data from 1,893 Spanish families from the Valencia, Sabadell, Asturias, and Gipuzkoa cohorts.

Pets as part of a child’s developmental environment

The researchers examined the presence of various types of pets —dogs, cats, birds, and “other animals” (rodents, fish, reptiles)— in households when children were aged 1 and 4–5 years, and explored possible links to emotional (“internalizing”) issues (such as anxiety, depression, or somatization) and behavioral (“externalizing”) issues (such as rule-breaking or hyperactivity) at ages 7–8.

After adjusting for multiple sociodemographic and family factors, the analyses revealed that continuous ownership of “other animals” (such as fish, turtles, or hamsters) was associated with a protective effect against emotional problems, while having cats only at ages 4–5 showed a mild association with more emotional or behavioral symptoms. No significant differences were observed for dogs, birds, or for owning any pet in general.

Beyond the numbers

“These findings do not necessarily imply causality—other unmeasured factors like attachment to the pet, loss of animals (and the grief this may cause), living conditions, or parenting differences could also play a role,” explains Llúcia González, CIBERESP researcher at Fisabio and first author of the paper.

In other words, the association between owning a cat at ages 4–5 and a higher risk of emotional or behavioral symptoms in middle childhood “should be interpreted with caution.” “There may be selection biases (for instance, certain family profiles might be more likely to have cats), changes in pet care, or differences in how parents perceive their child’s behavior,” adds Marisa Estarlich, co-author and researcher at Fisabio, UV, and CIBERESP.

Conversely, the apparently protective effect of “other animals” (rodents, fish, reptiles, etc.) suggests that less demanding pets might help create more stable relationships, potentially enhancing children’s psychological well-being.

“Including these animals in daily routines may help children develop responsibility in an environment that fosters affection and empathy,” notes Ainara Andiarena, researcher with the BEHRG Group at EHU.

Another author, Blanca Sarzo (CIBERESP), concludes that “to strengthen these findings, it would be useful to replicate the study with a larger sample and a broader age range to assess long-term effects.”