Narrated Anas:

Allah's Apostle went to the daughter of Milhan and reclined there (and slept) and then (woke up) smiling. She asked, "O Allah's Apostle! What makes you smile?" He replied, (I dreamt that) some people amongst my followers were sailing on the green sea in Allah's Cause, resembling kings on thrones." She said, "O Allah's Apostle! Invoke Allah to make me one of them." He said, "O Allah! Let her be one of them." Then he (slept again and woke up and) smiled. She asked him the same question and he gave the same reply. She said, "Invoke Allah to make me one of them." He replied, ''You will be amongst the first group of them;
you will not be amongst the last." Later on she married 'Ubada bin As-Samit and then she sailed on the sea with bint Qaraza, Mu'awiya's wife (for Jihad). On her return, she mounted her riding animal, which threw her down breaking her neck, and she died on falling down.

حَدَّثَنَا عَبْدُ اللَّهِ بْنُ مُحَمَّدٍ، حَدَّثَنَا مُعَاوِيَةُ بْنُ عَمْرٍو، حَدَّثَنَا أَبُو إِسْحَاقَ، عَنْ عَبْدِ اللَّهِ بْنِ عَبْدِ الرَّحْمَنِ الأَنْصَارِيِّ، قَالَ سَمِعْتُ أَنَسًا ـ رضى الله عنه ـ يَقُولُ دَخَلَ رَسُولُ اللَّهِ ﷺ عَلَى ابْنَةِ مِلْحَانَ فَاتَّكَأَ عِنْدَهَا، ثُمَّ ضَحِكَ فَقَالَتْ لِمَ تَضْحَكُ يَا رَسُولَ اللَّهِ فَقَالَ " نَاسٌ مِنْ أُمَّتِي يَرْكَبُونَ الْبَحْرَ الأَخْضَرَ فِي سَبِيلِ اللَّهِ، مَثَلُهُمْ مَثَلُ الْمُلُوكِ عَلَى الأَسِرَّةِ ". فَقَالَتْ يَا رَسُولَ اللَّهِ، ادْعُ اللَّهَ أَنْ يَجْعَلَنِي مِنْهُمْ. قَالَ " اللَّهُمَّ اجْعَلْهَا مِنْهُمْ ". ثُمَّ عَادَ فَضَحِكَ، فَقَالَتْ لَهُ مِثْلَ أَوْ مِمَّ ذَلِكَ فَقَالَ لَهَا مِثْلَ ذَلِكَ، فَقَالَتِ ادْعُ اللَّهَ أَنْ يَجْعَلَنِي مِنْهُمْ. قَالَ " أَنْتِ مِنَ الأَوَّلِينَ، وَلَسْتِ مِنَ الآخِرِينَ ". قَالَ قَالَ أَنَسٌ فَتَزَوَّجَتْ عُبَادَةَ بْنَ الصَّامِتِ، فَرَكِبَتِ الْبَحْرَ مَعَ بِنْتِ قَرَظَةَ، فَلَمَّا قَفَلَتْ رَكِبَتْ دَابَّتَهَا فَوَقَصَتْ بِهَا، فَسَقَطَتْ عَنْهَا فَمَاتَتْ.