An absolutely true, correct and technical answer is yes, there is hope, and even a certainty that one day that will be possible.
A practical answer is that your iPhone will be hit by an asteroid, before your newborn will get to see those pictures.
Apart from the obvious issue with decryption being difficult, even if technology appears in 30 years, it is unlikely that there will be readily available technology to read that iPhone then. And even if you also store a PC with all the necessary software by then, the storage in your phone is not meant to last 30 years, even if not used. Electrons are lost slowly but surely until all your data is spread in the universe. If you'd want to slow this process, you should keep the phone charged in a cold and dry environment, and still take the phone out once in a while to recharge it. Even like this, it is still more likely that by the time the technology will be available, the information will be corrupted beyond repair.
Disclaimer: Never believe when people tell you what the future will be like. 30 years ago really smart people thought we'd have holograms and that 640KB is enough memory for anyone in the world (corrected based on comment). We're still working on those holograms, and your iPhone has a million times more memory than 640KB (ok, only the most expensive one).
The lesson is, as many people already said, but it's a lesson worth repeating:
Remember to always back up!