A LEADING Hong Kong psychiatrist who read the Family Affairs article on depression in teenagers two weeks ago has responded with an important observation. With more pressure on children from a younger age nowadays, he warns, children as young as seven can suffer depression. If the signs of depression as outlined in the article (available at www.scmp.com ) seem to apply to your child, even though they might be a pre-teen, take them seriously. ANOTHER warning from a doctor: in the fierce summer heat, don't make the mistake of thinking tanning lotion allows you to spend more hours in the sun. The doctor says: 'Sun block is often misused because people using it think it is safe to stay in the sun much longer than they would [otherwise].' Skin cancer has been linked to sunburn as a child. Even when using a high-factor sun block, exposure to the sun's strongest rays between 11am and 3pm should be limited to less than an hour. If your child is swimming or sweating the lotion needs to be reapplied every hour.