It often begins during puberty
Hoarding behavior often begins during adolescence (around age 13 or 14), although it's possible for even young children to exhibit tendencies by holding onto old, broken toys or useless scraps of paper [source: Mayo Clinic]. Typically, severity increases with age and actually reaches unmanageable levels more often in older men and women [source: AARP]. In fact, it's a serious issue among the retired population, many of whom are less likely to be supervised on a regular basis (they are adults, after all). Often, the problem goes unnoticed until a grown child realizes what's going on.