My four year old reacts badly to insect bites and we are surrounded by tick infested woods! He had a very bad reaction to a tick bite on the inside of his upper thigh. Under the bite there was a hard knot that was jelly bean size. The lymph nodes nearby were swollen and redness extended in a circle around the bit and down his leg for six inches. I alternated organic peppermint essential oil and organic lavender essential oil neat (not diluted) every couple of hours the first day. It was hugely improved by the next day. I continued several times a day for another day. Now it is about gone and the gland swelling is reducing and I am treating it morning and night. I am giving him garlic throughout the day for a natural antibiotic just in case and will continue that for two weeks and maybe all through tick season.
Cedar essential oil and geranium essential oil, mixed with other oil is a good tick repellent. Last summer I put 2 cups of water and 20 drops of geranium in a spray bottle. We would spray children before they went outside. (It won't last all day, unfortunately. ) It really helped. My son sprayed his body and upper legs but not his shoes and socks. He stepped into a deer tick nest and had 100 ticks crawling all over his legs, but none went up past the sock line.
Thyme essential oil will kill a tick that is on you. One drop. (Lavender is safer, but slower for small children since thyme is very strong.)
Last summer my teenage son had a whole bunch (maybe 30?) of tick bites on a leg (he didn't spray! ) They became pimple like with white heads and the leg was red. I used charcoal poultices and chamomile poultices on the leg and it helped very quickly. I would mix either with warm water and wrap in a paper towel or cloth and attach to the leg with plastic wrap and then masking tape. I would use charcoal on the leg overnight. This worked very well to heal the leg.
I read that Geranium essential oil is a good to repel mosquitoes.
I tried this out and it really works! It also smells good. In the summertime, I always get eaten by these blood suckers and hate spraying chemical on myself. I cup my hand and filled it with water and mix in a drop or 2 of the Geranium essential oil. Rub it on my arms/legs/neck. You can buy Geranium oil at a health food store.