1. I have been unable to find any details of Leopold and Therese’s wedding however we can assume it was a year or two before their first child was born so probably 1852 or 1853. Working back from their ages given on their funeral notices we can determine their birth dates and their relative ages when they got married. Leopold was substantially older than Therese.
2. Jakob & Caroline Schlesinger got married on 9 October 1831 in Buda. See marriage register in FamilySearch
3. For more about Jewish Buda see Frojimovics, Kinga et al (1999) Jewish Budapest : monuments, rites, history
4. Jakob Schlesinger first appears in the records as a doctor in 1849 where he is listed as a 3rd category of doctor. I am not certain what this category means. See Hungaricana. He is listed as a medical doctor but not given the title “Dr.” which may suggest he is untrained. Perhaps he learnt his trade “on the job” during the wars of 1848-49?
5. In 1851 Jakob Schlesinger is listed under doctor of medicine at Tabakgasse 393. See Hungaricana. Today this is address is Dohany utca. In 1859 he is listed at Landstrasse 9 (nowadays Károlyi korut) (see Hungaricana) . From 1860 until 1874 he is listed at Landstrasse 45.
6. In Payne (1898) Berühmte Klavierspieler der Vergangenheit und Gegenwart Eine Sammlung von 123 Biographien und 121 Porträts Fanny is said to have “enjoyed her mother's musical instruction at an early age and showed a joyful affection for music.”
7. Leopold Mahler first appears in the Budapest address book in 1861 where he is listed as a stockbroker in cereals. Two addresses are given Dreikronengasse 6 (nowadays Herceg Primas) and Palatingasse 25 (Nador utca). Presumably one is a home address and one a work address but it is not clear which is which. He remains at Palatingasse 25 until 1871 (see Hungaricana), the year in which they move to Vienna.
8. Rudolfplatz 1 is the address given on Fanni’s enrolment form at the Conservatoire (early 1870). Leopold is not listed at this address in the 1870 or 1871 address book but is listed at this address in 1872 as an exporteur (see Lehmann’s 1872). The Mahlers appear to have retained a property in Budapest as Leopold is listed in the Budapest 1873 address book living at Aldergasse 8 (nowadays Sas utca). See Hungaricana
9. Leopold Mahler, kaufmann mit gattin aus Wien (businessman with wife from Vienna) booked into the Hotel zur Post in Ischl on the 11 or 12 September 1873. See Ischl Fremden Liste, 18 Sept 1873. There is another Leopold Mahler who owns a spinning mill in Prague who also visits the hotel but I believe this is our Leopold and Therese. Therese revisits the hotel with Fanni 8 years later.
10. Leopold Mahler moves to Neuthorgasse 9, Vienna in 1876 and then Roszauergasse 7, Vienna in 1877-1886 (see Lehmann’s). In 1888 he is listed at Lietchensteinstrasse 14. No occupation is given suggesting he has retired aged 75. They remain in Lietchensteinstrasse 14 until 1900, the year in which Leopold dies.
11. Leopold Mahler died 14 June 1900 aged 83. It was reported that Fanni missed a concert in the Reichpost , 19 April 1900 due to her father’s illness. The death of her father was reported in the Neues Wiener Tagblatt 15 June 1900 and Illustrirtes Wiener Extrablatt, 15 June 1900. The funeral notice appeared in Illustrirtes Wiener Extrablatt, 16 June 1900
12. Frau Therese Mahler books in to Perneckerstrasse 2 with Gustav etc. on 9 July 1901. See Ischler Cur-liste 9 July 1901. The party is a total of 9 persons - Gustav, Sophie, Valerie, Paula, Therese plus enkelin (granddaughter i.e. Lily) und dienerschaft (servants plural).
13. Emil Schlesinger (22 years old) and Valerie’s husband Albert Landau arrive together on 10 August. See Ischler Cur-liste 10 Aug 1901
14. Schwester (sister) Frau Mahler stays in Puchen 26 in Aussee with Gustav etc. on 7 July 1902. See Aussee Cur-list 7 July 1902. This time Gustav is listed as “disponent” which confirms that the Gustav Schlesinger that is listed as a disponent in the address book is part of our family.
15. Frau Gustav Schlesinger (i.e. Sophie) with mutter (Therese) und tochter (Paula) booked into the Hotel Erzehog Franz Karl in Aussee on 16 July 1903 (Aussee cur-liste 16 July 1903) where Ludwig and Fanni had booked in on 2 July (Aussee cur-liste 2 July). Five days later they booked into Puchen 71 (see Aussee cur-liste 21 July 1903). Without the ability to book online you had no way of booking accommodation so you might stay a few nights in a hotel while you find a suitable guest house or villa.
16. Therese died on 13 June 1913. Her death was reported in Die Ziet, 14 June 1913 and Neues Wiener Tagblatt 14 June 1913. Her funeral notice gives the mourning house as Porzellangasse 58. I cannot find the source of the funeral notice but a copy of it is available on Geni.