| Characteristic | n |
| Parents’ age range |
|
| Mothers (aged 28 - 38 years) | 7 |
| Fathers (aged 31 - 43 years) | 3 |
| Infants’ sex |
|
| Female | 6 |
| Male | 4 |
| Infants’ age range |
|
| 2 - 6 months | 5 |
| 7 - 12 months | 1 |
| 13 - 18 months | 3 |
| 19 - 24 months | 1 |