Keep gates at both ends of a flight of stairs to protect your baby from falls. Walkers are a great diversion for infants, but they provide no developmental benefit. Infants don't learn to walk by being in walkers. A walker may provide an infant with a significant increase in mobility which can be a danger if he is left unsupervised even briefly. An 8 month old scooting around the room at lightening speed sitting in his walker may have access to items on shelves or table tops which he couldn't get to previously.
Walkers are a particular danger near stairs.
When a child falls down the stairs in a walker, the walker prevents his natural protective reflexes from breaking the fall. Walkers may tip over on carpeted floors if the infant struggles to move a walker stuck in the carpeting. Never place your infant in a walker unless you intend to stay by his side the whole time he is in it. Guns pose a danger to children of any age. A loaded gun should never be kept anyplace where any child has access to it.