First congratulations on being so thoughtful to keep his plant alive for him. I do see brown tips on the leaves and this could be from lack of water but also from using water that has a lot of flouride or other chemicals. Tap water often has this problem. If you really want to pamper that plant buy some distilled water from the grocery store and water when the soil feels slightly dry to the touch. This will change from every few days to maybe once a week depending on the weather and soil. You can add some Osmocote to the container as the slow release action will not harm the plant or cause brown tips the way some liquid plant foods might. As long as you keep the soil moist you can be confident that new growth with healthy leaves will appear soon. Keep growing, Marianne Binetti