<p>A child can eat 1-2 holly berries (<em>Ilex</em>) without harm, but around 20 berries can cause death, so eating holly berries is a serious concern for children and pets. Though the berries are the part that is most commonly eaten, the bark, leaves, and seeds are toxic. What is the poison? Interestingly enough, it is theobromine, an alkaloid that is related to caffeine. Theobromine is <a href="https://www.thoughtco.com/theobromine-chemistry-structure-606832" data-component="link" data-source="inlineLink" data-type="internalLink" data-ordinal="1">found in chocolate</a> (and is toxic to dogs even at the lower concentration), but there is much more of the compound in holly berries.</p>The beautiful poinsettia is not something you want on a salad, but this <em>Euphorbia</em> is not particularly dangerous. If you eat a few leaves, you may feel ill or vomit. Rubbing the sap from the plant into your skin can give you an itchy rash. Beyond that, this plant is unlikely to cause a problem for either humans or pets.<p>Mistletoe is a name given to one of several plants, all potentially dangerous for kids and pets. <em>Phoradendron</em> species contain a toxin called phoratoxin, which can cause blurred vision, nausea, abdominal pain, diarrhea, blood pressure changes, and even death. The <em>Viscum</em> species of mistletoe contain a slightly different cocktail of chemicals, including the poisonous alkaloid tyramine, which produce similar symptoms. All <a href="https://www.thoughtco.com/is-mistletoe-really-poisonous-606132" data-inlink="61P6qfzLBcYicurcMrAAbw&#61;&#61;" data-component="link" data-source="inlineLink" data-type="internalLink" data-ordinal="1">parts of the mistletoe plant</a> are poisonous, though it is the berries that may be most attractive to kids. Eating 1-2 berries probably will not cause a problem for a child, but a small pet could be endangered by eating a few leaves or berries. If your child or pet eats mistletoe, it&#39;s a good idea to seek medical advice.</p>An amaryllis bulb is a common holiday gift. Amaryllis, daffodil, and narcissus bulbs may be forced indoors to produce showy holiday flowers. Eating the bulbs (and leaves, though they are less toxic) can cause abdominal pain, cardiac arrhythmias, and convulsions. The plants are more likely to be eaten by pets than children, but the alkaloid poison lycorine is considered toxic to humans, too.<p>Cyclamen (<em>Primulaceae</em>) is <a href="https://www.thoughtco.com/parts-of-a-flowering-plant-373607" data-inlink="Ti-LVkIVBd4mFsBHTakqOA&#61;&#61;" data-component="link" data-source="inlineLink" data-type="internalLink" data-ordinal="1">a flowering plant</a> commonly seen around the winter holidays. Cyclamen tubers contain triterpinoidsaponins, which can cause nausea, vomiting, convulsions, and paralysis. This plant is more of a concern for pets than humans. In fact, some cyclamen cultivars are favored for their delicate flavor and use in tea.</p>Cedars, pines, and firs are very mildly toxic. The biggest concern here is the possibility of puncturing part of the gastrointestinal tract from eating needles, though the tree oils may cause irritation of the mouth and skin. Toxicity might be affected by whether the tree had been sprayed with a flame retardant. People don&#39;t usually eat Christmas trees. Even a dog is unlikely to eat enough of the tree to cause a problem.The Jerusalem cherry (<em>Solanum pseudocapsicum</em>) is a species of nightshade that bears poisonous fruit. The primary poison is the alkaloid solanocapsine, which can cause gastric upset and vomiting in people, but generally is not life-threatening. However, the fruits are extremely toxic to dogs and cats and some birds. The fruit resembles a cherry tomato, both in appearance and flavor, so kids and pets may eat enough to cause illness, or in the case of pets, even death.